Description And Operation
DESCRIPTION
The power mirror system is comprised of the following components:
| 1. | Refer to BODY CONTROL MODULE (BCM) . |
| 2. | Refer to INSTRUMENT PANEL CLUSTER (IPC) . |
| 3. | Refer to COMBINED REAR VIEW MIRROR MODULE (CRVMM) . |
| 4. | Refer to POWER OUTSIDE REAR VIEW MIRRORS . |
| 5. | Refer to POWER MIRROR SWITCH . |
OPERATION
Communication
The IPC determines the ignition status and the gear status based on their associated CAN network signals. The IPC will transmit the enable/disable signal over the LIN bus to the CRVMM. The internal CRVMM will read the internal signal for the sensor values and determine the ratio between the forward and backward light intensity, along with the enable signal coming from the BCM, to determine the reflecting mode. The CRVMM then sends the internal Electrochromatic (EC) mirror status signal over the LIN bus. The IPC receives the signal from the CRVMM to determine if errors have been reported by the CRVMM.
| Refer to COMPONENT INDEX . |
Power mirror system power supply comes from BCM, through the line protected by fuse located in the BCM.
When reverse gear is engaged, the switch closes and sends the control signal to the mirror from the BCM.
| Refer to COMPONENT INDEX . |
The CRVMM receives the enable command over LIN bus from the IPC to enable the EC mirror. The CRVMM returns the EC mirror status over LIN bus to the IPC.
On vehicles equipped with the EC mirror, the electrochromatic feature automatically changes reflectance of the internal to provide maximum night vision, while giving relief from glare by headlamps from the rear of the vehicle during night driving.
A photo-light sensor located internally in the front and back side of the mirror indicate the light intensity in front of the driver and from behind the driver.
The ambient photocell light sensor faces forward, to detect the outside light levels. The headlamp photocell light sensor (2) is located on the mirror face to one side of the switch and facing rearward, to detect the light level received at the rear window side of the mirror. When the difference between the two light levels becomes too great (the light level received at the rear of the mirror is much higher than that at the front of the mirror), the mirror begins to darken. The mirror also monitors the backup lamp circuit, and will automatically disable its self-dimming feature whenever the transmission gear selector is in the REVERSE position.
The CRVMM will turn the EC mirror button backlight to ON or to OFF the when the EC mirror function is enabled or disabled with the EC mirror hard button.
Auto Mode - This feature will start automatically when the IPC determines that the ignition status is RUN is true, however the reflectance ratio of the CRVMM is determined according to the two modes (ON mode and OFF mode).
ON Mode - This feature will start automatically when the IPC determines that the ignition status = RUN and that the transmission (automatic or manual) is engaged in the reverse gear. Once the IPC determines the status of those bus messages, the IPC sends a LIN bus message to the CRVMM to turn the EC mirror on. For MP only, the CRVMM hard button is enabled (on) in order for the feature to enter into ON Mode. Once in ON mode, the CRVMM will set the reflectance output to low reflectance.
The EC mirror will be disabled and enter OFF mode if one of the following scenarios are true:
- When the ignition status = RUN
- When the EC feature is OM and the vehicle enters into REVERSE gear.
- The PRND status LIN signal is not available (SNA error).
- The EC mirror hard button is disabled (OFF).
| Refer to COMPONENT INDEX . |
The IPC sends a request to activate the EC feature by transmitting a message over the LIN bus communications network to the CRVMM.
The CRVMM turns on the feature and responds back to the IPC with another bus message indicating that the EC is enabled.
The IPC sends a LIN PRND message to the CRVMM. The PRND is acquired by the IPC over the bus network by its own gear status indication as well as a CAN C bus shift lever position message.
The CRVMM does not need to utilize the PRDN signal but it can use this signal to enable or disable the dimming feature based on PRND reverse status.
| Refer to COMPONENT INDEX . |
The power mirror switch circuitry within the driver side front door power switch receives power from the BCM. The power mirror switch circuitry also has a path to ground at all times through a take out and eyelet terminal of the body wire harness that is secured to the body sheet metal. Mirror switch voltage supply is from the Power Distribution Center (PDC). The backlighting for the switch is an input from the IPC. The mirror switch has two Light Emitting Diode (LED) lights to indicate which outside mirror has been selected for adjustment.
The power mirror control switch determines which motor will be energized and the direction in which the motor will be driven.
The latching power mirror switch has three positions:
- Driver
- Passenger
- Neutral
The non-latching mirror adjustment switch has four positions:
- Up
- Down
- Left
- Right
| Refer to COMPONENT INDEX . |
The door mirrors can be electrically adjusted in two directions using a joystick control located in the door control switch bank on the driver side: a selection knob makes it possible to choose either the left or the right mirror. The joystick controls two electrical motors located in each of the two mirrors.
One motor in each mirror controls horizontal (left and right) movement, while the second motor controls vertical (up and down) movement.
Each power mirror articulation mechanism is driven by two individual Direct Current (DC) reversible electric motors. The mirror motors also incorporate clutches that protect the motor by disengaging the drive whenever the travel limits of the swivel have been reached. When battery current and ground are output from the control switch to the two motor terminals, the motor rotates in one direction. When the switch output polarity to the motor connections are reversed, the motor rotates in the opposite direction.
Turn signal control is managed by the BCM while the Blind Spot Monitor (BSM) indicator is managed by the BSM module located within the tail lamp.